Owing to a widespread use of an Internet in recent years, it is allowed to receive data contents through the Internet by connecting a variety kinds of information equipment to the internet.
By adding, for example, an Internet connection function to a digital TV receiver, it is allowed to receive and display not only the data contents but also the digital TV signals (stream data) broadcast via, for example, a satellite by using the digital TV receiver.
When the Internet connection function is added to the digital TV receiver, however, the data contents received through the Internet may make a reference to a program (stream contents) that is on air for TV broadcast, whereby the data contents can be displayed on a screen and, at the same time, the TV images can be displayed as stream contents referred to by the data contents.
As a result, when there are, for example, conflicting sponsors, i.e., a sponsor A providing data contents and a sponsor B providing stream contents, there may take place such an undesired situation that the two contents provided by the conflicting sponsors are simultaneously displayed.
Further, the copyright of the image contents may be infringed if predetermined stream contents (image contents) are intentionally referred by the data contents.